<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
        "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <meta charset="UTF-8">
    <title>Hello HTML!</title>
</head>
<body>
<!--这是一段注释。注释不会在浏览器中显示。-->
<p a="b" style="color: red">你好，HTML！</p>
<p><a href="frame_a.html" target="showframe">Frame_a<a></p>
<p><a href="frame_b.html" target="showframe">Frame_b<a></p>
<p><a href="frame_c.html" target="showframe">Frame_c<a></p>
<iframe frameborder="1" height="600" name="showframe" src="https://www.baidu.com/" width="600"/>
<hr/>
</body>
</html>
